- any of certain gems having a chatoyant luster, especially chrysoberyl.
- a playing marble marked with eyelike concentric circles.
- cat eye.
- any of a group of gemstones, esp a greenish-yellow variety of chrysoberyl, that reflect a streak of light when cut in a rounded unfaceted shape
- a grazing marine gastropod, Turbo smaragdus, of New Zealand waters
- a glass reflector set into a small fixture, placed at intervals along roads to indicate traffic lanes at night
